1. Field of the Invention
This invention generally relates to human body joint motion evaluation and, more particularly, to a system and method for converting inertial measurement unit (IMU) sensor measurements into physiologically defined joint rotation measurements in a standard format more easily understood by health care professionals.
2. Description of the Related Art
Measuring a body joint's range of motion (RoM) is critical for applications such as joint surgery recovery and sports technique coaching. It is also important for orthopedic patients to begin flexing the repaired joint soon after surgery is completed. Often the patient does not understand or correctly comply with the doctor's recovery instructions, and upon returning to their home, the patient is not sufficiently monitored by medical staff to determine if recovery is proceeding well. This lack of monitoring may result in poor RoM and the need for additional surgeries. It would also be advantageous to monitor range of motion dynamically, during normal daily activities. Many existing systems only measure statically, when the user is still and focused specifically on the measurement process.
Currently existing systems do not use physiologically modeled joint rotation decomposition to determine constituent joint rotations. They also are only capable of displaying a single planar rotation, and cannot calculate or display each of the constituent rotations that makeup the composite rotation. They require trained professionals to perform the measurement. They do not automatically adapt their analysis to the specific joints that are being measured. They do not show trending over time during normal daily usage. They are not able to send trending information to remote viewers. Many existing systems only measure statically, when the user is still and focused specifically on the measurement process.
It would also be advantageous to monitor range of motion dynamically, during normal daily activities, and present the measurements in an intuitive, easy to understand format.